废纸造纸废水处理工程的设计与运行

文章针对废纸造纸生产中废水产生量大,SS、COD浓度较高的问题,将废纸造纸废水处理工程实践中的污水作为对象,研究一套废纸造纸废水回收利用的污水处理方法,减少再生纸造纸工业对环境的污染。实验结果和工程实践证明:利用混凝沉淀—活性污泥相结合工艺处理废纸造纸废水,达到一部分经物理处理后回收利用,一部分经生化处理后达标排放。采用该工艺处理效果好,SS去除率达99.7%、COD去除率达98.4%,且运行稳定,成本和一次性投资均较低,其排放废水水质满足《造纸工业水污染物排放标准》(GB3544-2001)中的排放要求。     

为建设城市与农村再生资源回收利用体系而努力

大家都知道,当前气候变化问题引起了全球各国的普遍重视。从全球来看,应对气候变化、降低碳排放、节能降耗已成为一个全世界普遍关心的问题,也达成了一个共识,就是在今后的经济发展中要进一步节能     

将农业再生资源回收利用事业推向新高度

农业再生资源是再生资源的一个特殊而重要的组成部分,与其他品种再生资源相比,具有两大特点:一是产出量大,我国是农业大国,据统计,我国每年产生各类农作物秸秆约6.5亿t,畜禽粪便产生量约20亿     

废家电拆解处理研讨会在京举行

2010年1月8日,由中国再生资源回收利用协会(简称中再生协会)主办的废家电拆解处理研讨会在京举行。来自家电以旧换新活动9个试点省市的17家家电拆解企业     

地下水资源的合理开发利用

地下水是我国城市和工农业用水的主要供水水源。但是,目前我国地下水开发利用不够合理,不仅直接破坏了地下水资源,而且诱发了一系列环境地质问题及次生生态环境问题。本文提出应当把地下水环境容量作为地质环境目标管理的基本依据和地质环境保护规划的主要约束条件,从而将容量概念引入到地下水开发利用管理中的观点。     

Enzyme extraction by ultrasound from sludge flocs

Enzymes play essential roles in the biological processes of sludge treatment. In this article, the ultrasound method to extract enzymes from sludge flocs was presented. Results showed that using ultrasound method at 20 kHz could extract more types of enzymes than that ultrasound at 40 kHz and ethylenediamine tetraacetic acid (EDTA) methods. The optimum parameters of ultrasound extraction at 20 kHz were duration of 10 min and power of 480 W. Under the condition, ultrasound could break the cells and extract both the extracellular and intercellular enzymes. Ultrasound power was apparently more susceptive to enzyme extraction than duration, suggesting that the control of power during ultrasound extraction was more important than that of duration. The Pearson correlation analysis between enzyme activities and cation contents revealed that the different types of enzymes had distinct cation binding characteristics.     

Pollutants removal and simulation model of combined membrane process for wastewater treatment and reuse in submarine cabin for long voyage

A laboratory scale test was conducted in a combined membrane process (CMP) with a capacity of 2.91 m3/d for 240 d to treat the mixed wastewater of humidity condensate, hygiene wastewater and urine in submarine cabin during prolonged voyage. Removal performance of chemical oxygen demand (COD), ammonia nitrogen (NH4 +-N), turbidity and anionic surfactants (LAS) was investigated under di erent conditions. It was observed that the e uent COD, NH4 +-N, turbidity and LAS flocculated in ranges of 0.19–0.85 mg/L, 0.03–0.18 mg/L, 0.0–0.15 NTU and 0.0–0.05 mg/L, respectively in spite of considerable fluctuation in corresponding influent of 2120–5350 mg/L, 79.5–129.3 mg/L, 110–181.1NTU and 4.9–5.4 mg/L. The e uent quality of the CMP could meet the requirements of mechanical water and hygiene water according to the class I water quality standards in China (GB3838-2002). The removal rates of COD, NH4 +-N, turbidity and LAS removed in the MBR were more than 90%, which indicated that biodegradation is indispensable and plays a major role in the wastewater treatment and reuse. A model, built on the back propagation neural network (BPNN) theory, was developed for the simulation of CMP and produced high reliability. The average error of COD and NH4 +-N was 5.14% and 6.20%, respectively, and the root mean squared error of turbidity and LAS was 2.76% and 1.41%, respectively. The results indicated that the model well fitted the laboratory data, and was able to simulate the removal of COD, NH4 +-N, turbidity and LAS. It also suggested that the model proposed could reflect and manage the operation of CMP for the treatment of the mixed wastewaters in submarine.     

全国产品回收利用基础与管理标委会成立

从日前召开的全国产品回收利用基础与管理标准化技术委员会成立大会上获悉,一批涉及废旧产品和废弃物回收利用的国家标准正在加紧制定。     

电子废弃物物流及责任方安全职责分析

电子废弃物回收再利用属于逆向物流。阐述了我国电子废弃物物流的特点和模式,系统分析了电子废弃物物流框架,重点阐明在电子废弃物回收再利用中各责任方的安全职责：电子产品生产者具有全面责任;消费者具有经济责任和物质责任;政府管理部门具有宏观调控和监督协调责任;物流方有微观控制和安全保管的责任。     

建筑废弃物回收再利用项目运作模式刍探

建筑废弃物处理是城市建设中的一大难题,如果实行简单填埋,不仅污染环境、造成资源浪费,而且也耗费政府大量财力。介绍了深圳市龙岗区通过创新招标方式,公开出让特许经营权,引入企业运用先进技术对建筑废弃物实行综合再利用的一些做法,同时对城市建筑废弃物回收再利用如何实现规模化和产业化发展,以及政府在推动循环经济发展方面如何将经济效益与社会效益有机结合提出了一些看法。